Increment page view count in Wordpress

theme_set_post_views.php

function theme_set_post_views($id) {
  $count_key = 'theme_post_views_count';
  $count = get_post_meta($id, $count_key, true);

  if ($count == '') {
    $count = 0;
    delete_post_meta($id, $count_key);
    add_post_meta($id, $count_key, '0');
  } else {
    $count++;
    update_post_meta($id, $count_key, $count);
  }
}

// Usage:
// theme_set_post_views(get_the_ID());